Current collector, energy storage element, and method of manufacturing current collector

Abstract

A positive electrode current collector includes a terminal connecting portion, a first electrode connecting portion including a first surface extending forward and downward from a right frontal portion, a second electrode connecting portion including a second surface extending forward and downward from a left frontal portion and opposing the first surface, a first twisted portion having an end portion connected to the right frontal portion and the other end portion connected to an upper end portion, and a second twisted portion having an end portion connected to the left frontal portion and the other end portion connected to an upper end portion. A distance between the first surface and the second surface is larger than a distance between the center of the right frontal portion and the center of the left frontal portion.

1 . A current collector comprising:
 a terminal connecting portion;   a first electrode connecting portion including a first surface extending forward and downward from a right frontal portion of the terminal connecting portion;   a second electrode connecting portion including a second surface extending forward and downward from a left frontal portion of the terminal connecting portion and opposing the first surface;   a first twisted portion having an end portion connected to the right frontal portion and the other end portion connected to an upper end portion of the first electrode connecting portion; and   a second twisted portion having an end portion connected to the left frontal portion and the other end portion connected to an upper end portion of the second electrode connecting portion,   wherein a clearance between surfaces defined as a distance between the first surface and the second surface in a left-right direction is larger than a distance between the center of the right frontal portion in the left-right direction and the center of the left frontal portion in the left-right direction.   
     
     
         2 . The current collector according to  claim 1 ,
 wherein the clearance between surfaces is larger than a distance between the right edge of the right frontal portion and the left edge of the left frontal portion in the left-right direction.   
     
     
         3 . The current collector according to  claim 1 ,
 wherein the clearance between surfaces is defined as a distance in the left-right direction between an upper end portion of the first surface and an upper end portion of the second surface.   
     
     
         4 . The current collector according to  claim 1 ,
 wherein the clearance between surfaces is defined as a minimum value of the distance between the first surface and the second surface in the left-right direction.   
     
     
         5 . The current collector according to  claim 1 ,
 wherein a length of the right frontal portion in the left-right direction is generally the same as a length of the upper end portion of the first electrode connecting portion in a forward-backward direction, or a length of the left frontal portion in the left-right direction is generally the same as a length of the upper end portion of the second electrode connecting portion in the forward-backward direction.   
     
     
         6 . The current collector according to  claim 1 ,
 wherein the first twisted portion has a shape formed by twisting a flat plate in a plurality of stages, and constitutes an intermediate portion between the right frontal portion and the upper end portion of the first electrode connecting portion, or the second twisted portion has a shape formed by twisting a flat plate in a plurality of stages, and constitutes an intermediate portion between the left frontal portion and the upper end portion of the second electrode connecting portion.   
     
     
         7 . The current collector according to  claim 1 ,
 the current collector being provided in an energy storage element including (i) an electrode assembly having a positive electrode and a negative electrode, and (ii) a positive electrode terminal and a negative electrode terminal located above the electrode assembly,   wherein the terminal connecting portion is located on the side of the positive electrode terminal or the negative electrode terminal and electrically connected to the positive electrode terminal or the negative electrode terminal,   the first electrode connecting portion is connected to the positive electrode or the negative electrode via the first surface, and   the second electrode connecting portion is connected to the positive electrode or the negative electrode via the second surface.   
     
     
         8 . An energy storage element comprising:
 an electrode assembly having a positive electrode and a negative electrode;   a positive electrode terminal;   a negative electrode terminal; and   the current collector according to  claim 1 , electrically connecting at least one of between the positive electrode and the positive electrode terminal and between the negative electrode and the negative electrode terminal.   
     
     
         9 . A method of manufacturing a current collector,
 the current collector including:   a terminal connecting portion;   a first electrode connecting portion including a first surface extending forward from a right frontal portion of the terminal connecting portion; and   a second electrode connecting portion including a second surface extending forward from a left frontal portion of the terminal connecting portion,   the method comprising:   forming a first twisted portion having an end portion connected to the right frontal portion and the other end portion connected to an upper end portion of the first electrode connecting portion, by rotating and twisting downward the first electrode connecting portion with respect to the terminal connecting portion such that the first surface extends forward and downward from the right frontal portion; and   forming a second twisted portion having an end portion connected to the left frontal portion and the other end portion connected to an upper end portion of the second electrode connecting portion, by rotating and twisting downward the second electrode connecting portion with respect to the terminal connecting portion such that the second surface extends forward and downward from the left frontal portion so as to oppose the first surface,   wherein the forming of the first twisted portion or the forming of the second twisted portion includes twisting the first electrode connecting portion or twisting the second electrode connecting portion such that a clearance between surfaces a distance between the first surface and the second surface in the left-right direction becomes larger than a distance between the center of the right frontal portion in the left-right direction and the center of the left frontal portion in the left-right direction.   
     
     
         10 . The method according to  claim 9 ,
 wherein the forming of the first twisted portion or the forming of the second twisted portion includes twisting the first electrode connecting portion or twisting the second electrode connecting portion such that the clearance between surfaces becomes larger than a distance between the right edge of the right frontal portion and the left edge of the left frontal portion in the left-right direction.   
     
     
         11 . The method according to  claim 9 ,
 wherein the forming of the first twisted portion or the forming of the second twisted portion includes twisting the first electrode connecting portion or twisting the second electrode connecting portion such that the clearance between surfaces becomes equal to a distance between an upper end portion of the first surface and an upper end portion of the second surface in the left-right direction.   
     
     
         12 . The method according to  claim 9 ,
 wherein the forming of the first twisted portion or the forming of the second twisted portion includes twisting the first electrode connecting portion or twisting the second electrode connecting portion such that the clearance between surfaces becomes equal to a minimum value of the distance between the first surface and the second surface in the left-right direction.